Process of bleaching oils and fats.



UNITED STATES PATEN T ()FFIUE.

HERMAN A. METZ, OF BROOKLYN, N EYV YORK, AND PHILIP S. CLARKSON, OF

' BEVERLY, NEW JERSEY.

PROCESS OF BLEA CHING OILS AND FATS- Specification of Letters Patent.

Patented June 11, 1907.

Application filed Se t mber 27, 1905. Serial No. 280,365.

To a 7/)710777. it may concern:

Be it known that we, HERMAN A. Man, residing at Brooklyn, Kings county, New York, and PHILIP S. CLAmcsox, residing at Beverly, Burlington county, New Jersey, citizens of the United States, have invented certain new and useful Improvements in Processes of Bleaching Oils and Fats, of which the following is a specification.

This invention is aprocess of bleaching oils and fats, and consists essentially in subjecting them to the action of certain salts or compounds hereinafter referred to as formaldehyde hydrosuliites, by which term it is intended to include the compounds known as formaldehyde-hydrosuliites and sulfoxylates.

In the bleaching of various oils it has been usual to subject non-drying and semi-drying oils to the action of oxidizing agents, while in the case of drying oils reducing agents have been used. We have discovered that the compounds known as formaldehyde hydrosulfites exert a powerful bleaching action on oils and other fats, including those of all of the almve-mentioned classes. In the case of the non-drying oils the coloring matter is so effectively destroyed that when. the oil is subsequently sulfonated the decrease in color is as marked as in the original oil, indicating the actual destruction of the coloring matter; if the coloring matter were merely reduced the color would be restored by the operations connected with sulfonation.

In carrying our invention into effect according to one modification in which a sodium salt is used we proceed as follows: 200 parts corn oil are mixed with 600 parts cold water containing 10 parts of the materials commercially known as Hyraldite or hydrosulfite N F or equivalent parts of similar products, containin as its active con stituent a sodium formaldehyde hydrosulfite compound, NaHSO .C-I-I O. The mixture is churned thoroughly in a closed vessel, then heated to 70 C. and thereafter allowed to cool with frequent agitation. It is then allowed to stand and aft-er some hours the amber color of the oil will be changed to a pale straw color, and on further standing for 24 hours the color will be entirely destroyed. Other oils may be treated in a similar manner; for instance, raw linseed oil (the fresh oil from the seeds of Lin'um usitaii-ssimum) may be bleached as above described in the case of corn oil. After bleaching the oil is separated by decanting the upper layer of clear oil and washing out the remainder with petroleum spirit, or the whole of the bleached oil may be separated by means of a solvent which is afterward separated by distillation.

We claim 1. The method of bleaching oils and fats which consists in subjecting them to the action of a formaldehyde hydrosulfite, substantially as described.

2. The method of bleaching oils and fats which consists in subjecting them to the action of sodium formaldehyde hydrosulfitg, substanmfb d. W

In testimony whereof, we affix our signatures in presence oft wo witnesses.

HERMAN A. METZ. PHILIP S. CLARKSON. W'itnesses EUGEXE A. BYRNES, H. S. NEIMAN. 

